In the present application, the phrase "yarn guide means" describes those moved parts, including the traversing yarn guide, of a winding apparatus, which are so connected with the yarn guide, that they are all reversibly driven simultaneously with the yarn guide. Whereas the traversing yarn guide performs primarily a straight-line oscillating motion along the traversing stroke and transversely to the direction of the advancing yarn, and reverses its traveling direction in each stroke end, the other components of the yarn guide means, in particular the drive elements for converting the rotation of the drive, may also rotatably oscillate about a rotational axis. In so doing, they each reverse their direction at the stroke ends of the guide means. The term "yarn guide means" also describes the transmission elements, connecting elements, drive elements, etc. for the yarn guides of a winding apparatus with a plurality of winding positions, which are driven by a common drive, and which reverse with the yarn guides.
A winding appartaus as described above is disclosed in Swiss Pat. No. 432,324. The yarn guide, which is axially reciprocated between the ends of the traverse stroke by a drive eccentric, is braked by springs in the area of the stroke ends and again accelerated assisted by spring tension. To this end, the springs must each be differently biased with respect to the adjusted speed of the winding apparatus, so as to recover at the stroke reversal the kinetic energy of the yarn guide in precisely predetermined reversal points, as required in a winding machine.
DE-OS No. 25 36 296 discloses a winding machine wherein pistons are mounted on the yarn guide which is reciprocated by a cross-spiralled roll. These pistons immerse in stationary cylinders in the area of the stroke ends. In so doing, the air in the cylinders primarily escapes for the purpose of damping. However, it is also compressed in part for the purpose of recovering energy. The loss of energy results from the escaping air.
It is according an object of the present invention to improve the known yarn traversing apparatus so that the kinetic energy of the reversibly moved yarn guide means, which includes the yarn guide, can be recovered at the reversal of the motion, irrespective of the speed of the winding apparatus and without any adaptation to its speed.